公开(公告)号：US20250003037A1

公开(公告)日：2025-01-02

申请号：US18811384

申请日：2024-08-21

Applicant: ArcelorMittal

Inventor： Sebastian COBO ,  Emmanuel LUCAS ,  Matthieu SALIB ,  Guillaume STECHMANN

IPC: C22C38/04 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/14

Abstract: A steel sheet has a chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P≤0.040%, Ca≤0.01%, S≤0.006%, N≤0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 μm/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

公开(公告)号：US20250137105A1

公开(公告)日：2025-05-01

申请号：US18988516

申请日：2024-12-19

Applicant: ArcelorMittal

Inventor： Sebastian COBO ,  Emmanuel LUCAS ,  Matthieu SALIB ,  Guillaume STECHMANN

IPC: C22C38/04 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/14

Abstract: A steel sheet hasa chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P≤0.040%, Ca≤0.01%, S≤0.006%, N≤0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 μm/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

公开(公告)号：US20250137083A1

公开(公告)日：2025-05-01

申请号：US19011522

申请日：2025-01-06

Applicant: ArcelorMittal

Inventor： Alice DUMONT ,  Guillaume STECHMANN ,  Emmanuel LUCAS ,  Matthieu SALIB

IPC: C21D9/00 ,  C21D1/18 ,  C21D6/00 ,  C21D7/13 ,  C21D8/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32

Abstract: A steel sheet having a chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P≤0.040%, Ca≤0.01%, S≤0.006%, N≤0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk is topped by a skin layer occupying the outermost 10% of the thickness on either side of the bulk, the density of TiN/Ti(C,N) inclusions in the skin being smaller than 240 particles/mm2 and the clustering index of MnS inclusions in the skin being lower than 110 μm/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending angle normalized to 1.5 mm and measured in the transverse direction strictly greater than 48°.